Digital radio with vocoding encrypting codec

Abstract

A new digital radio includes codec, vocoder and encryption/decryption processing all on a single integrated circuit chip module. Great flexibility is provided in terms of different operating modes (e.g., encrypt/decrypt only, vocode only, or encrypt/decrypt and vocode). Radio control processor overhead is reduced substantially, because the radio control processor does not need to transfer data between codec, vocoder and encryption/decryption processes and/or components. An internal executive routine within the module handles all vocoder and encryption command and data processing. A special synchronization scheme is provided to synchronize the transceiver modem rate with the speech processing rate. The single-chip speech processing module is sufficiently flexible to allow users to define, write, load and use their own encryption/decryption routines without requiring a new masked ROM.

What is claimed is: 
     
       1. In a radio commnunications system, a single chip speech processing module having an analog speech signal connection, a data connection, an analog signal processor connected to the analog speech signal connection and a digital signal processor connected to the data connection, said single chip speech processing module comprising: a converter within the analog signal processor for performing a CODEC function of converting between said analog speech signals and first digital speech signals;   the digital signal processor being connected to said analog signal processor and including means for processing a stream of speech information in real time by synchronously performing the following functions: converting between said first digital speech signals and vocoded digital speech signals: and   for converting between said vocoded digital speech signals and encrypted digital speech signals; and     wherein the module further includes data input/output circuitry connected between said digital signal processor and said data connection for coupling said encrypted digital speech signals between said digital signal processor and said data connection.   
     
     
       2. A method for processing speech signals in real time within a single chip mixed signal speech processing module, said single chip mixed signal speech processing module having at least one analog speech signal pin and at least one data connection pin, said method comprising the following steps: (a) converting between said analog speech signals and first digital speech signals;   (b) converting between said first digital speech signals and vocoded digital speech signals;   (c) converting between said vocoded digital speech signals and encrypted digital speech signals;   (d) coupling said encrypted digital speech signals to/from said data connection; and   (e) synchronizing said steps (a)-(d) within the chip so as to process a stream of speech information in real time.   
     
     
       3. A digital radio comprising: at least one audio source providing analog signals;   a single chip mixed signal speech processing module connected to receive said analog signals, said speech processing module performing the following functions: (a) converting said analog signals to digital signals,   (b) compressing said digital signals into compressed digital signals,   (c) encrypting said compressed digital signals,   (d) outputting said encrypted, compressed digital signals; and   (e) synchronizing said steps (a)-(d) within the chip to process a stream of speech information in real time and     RF transmitting circuitry connected to receive said encrypted compressed digital signals outputted by said single chip speech processing module, said RF transmitting circuitry generating a radio signal containing said encrypted, compressed digital signals and transmitting said radio signal over the air.   
     
     
       4. A digital radio comprising: at least one audio destination requiring an output analog signal;   RF transceiving circuitry for transmitting RF signals over the air and for receiving RF signals transmitted over the air;   a control microprocessor connected to control said RF transceiving circuitry; and   a memory limited mixed signal speech processing chip coupled to said control microprocessor and to said input and output analog signals, said speech processing chip including an analog signal processor and a digital signal processor, said speech processing chip for: (a) converting said input analog signal to a digital signal,   (b) compressing said digital signal,   (c) encrypting said digital signal; and   (d) synchronizing said steps (a)-(c) to process a stream of speech information in real time.     
     
     
       5. A digital radio communications system including: an antenna;   a radio frequency transceiver section connected to said antenna;   a speech processing module comprising a mixed signal integrated circuit having an analog signal processor and a digital signal processor; and   a control processor coupled to said radio frequency transceiver section and said speech processing module, said control processor for coupling digital data between said radio frequency transceiver and said speech processing module;   wherein said speech processing module is controllable by said control processor to perform any/all of the following functions in a synchronized manner in real time for a stream of speech information: (a) encrypt or decrypt said digital data,   (b) compress or expand said digital data, and   (c) convert between analog signals and digital data.     
     
     
       6. A system as in claim 5 wherein said control processor writes a command to said speech processing module, said command specifying which functions said speech processing module is to perform. 
     
     
       7. A system as in claim 6 wherein one of said commands is to cut samples. 
     
     
       8. A system as in claim 6 wherein one of said commands is to add samples. 
     
     
       9. A speech processing system including: a mixed signal processing integrated circuit including a digital signal processor and an analog signal processor,;   a read only memory for storing program control instructions for execution by said digital signal processor, the program control instruction including at least a vocoding routine and an encryption routine;   a random access memory coupled to said digital signal processor; and   loading and controlling means coupled to said random access memory for loading further encryption program control instructions into said random access memory, and for controlling said digital signal processor to execute said further encryption program control instructions in addition to or in lieu of said encryption routine stored in said read only memory.   
     
     
       10. A speech processing system as in claim 9 wherein said loading and controlling means includes means for loading a jump table into said random access memory, said jump table directing at least some program calls by said digital signal processor to program instructions stored in said read only memory, and directing at least some other program calls by said digital signal processor to program instructions loaded into said random access memory. 
     
     
       11. A digital radio including: means for transmitting and receiving RF signals; and   a speech processing module including a digital signal processor, an analog signal processor and a program store, said analog signal processor performing a CODEC operation, said program store storing first and second sets of program control instructions, said digital signal processor executing said first set of program control instructions to perform encryption and decryption, said digital signal processor executing said second set of program control instructions to perform vocoding, said digital signal processor synchronizing execution of said first and second sets of program control instructions to encrypt or decrypt and vocode a digitized speech data stream in real time.